Multiple materials with different textures
Not entirely sure what you mean. From the screenshot it looks like you have several meshes, one for each texture. What is "material display mode"? You can have different textures applied to the same mesh without splitting the mesh up like you have done. I think that might be what you need to do if you want them to show up all at once. Like this.



Edit: To explain a little better. Here The red material has no textures, the green material has one texture (cloud) and the blue material has two textures (cloud and noise) Hope that helps.